node.js - socket.io with express generator -

before write tried solution @ using socket.io in express 4 , express-generator's /bin/www

the terminal show error on /routes/messages.js:12

io.on('connection', function(socket){ typeerror: cannot read property 'on' of undefined 

here comes files:

/routes/messages.js

var express = require('express'); var controller = require('../controllers/messagecontroller'); var passport = require('passport'); var router = express.router();   router.get('/', controller.plain);  module.exports = function(io){   var router = express.router();    io.on('connection', function(socket){     console.log('**********************************************************');     console.log('mensaje desde socket.io en el archivo de rutas messages.js');     console.log('**********************************************************');   });   return router; }; 

/bin/www

#!/usr/bin/env node /**  * module dependencies.  */  var app = require('../app'); var debug = require('debug')('archiers:server'); var http = require('http');  /**  * port environment , store in express.  */  var port = normalizeport(process.env.port || '3000'); app.set('port', port);   /**  * create http server.  */ var server = http.createserver(app);  // socket.io  var io = app.io; io.attach(server);  /**  * listen on provided port, on network interfaces.  */  server.listen(port); server.on('error', onerror); server.on('listening', onlistening);  /**  * normalize port number, string, or false.  */  function normalizeport(val) {   var port = parseint(val, 10);    if (isnan(port)) {     // named pipe     return val;   }    if (port >= 0) {     // port number     return port;   }    return false; }  /**  * event listener http server "error" event.  */  function onerror(error) {   if (error.syscall !== 'listen') {     throw error;   }    var bind = typeof port === 'string'     ? 'pipe ' + port     : 'port ' + port;    // handle specific listen errors friendly messages   switch (error.code) {     case 'eacces':       console.error(bind + ' requires elevated privileges');       process.exit(1);       break;     case 'eaddrinuse':       console.error(bind + ' in use');       process.exit(1);       break;     default:       throw error;   } }  /**  * event listener http server "listening" event.  */  function onlistening() {   var addr = server.address();   var bind = typeof addr === 'string'     ? 'pipe ' + addr     : 'port ' + addr.port;   debug('listening on ' + bind); } 

/app.js

var express = require('express'); var path = require('path'); var favicon = require('serve-favicon'); var logger = require('morgan'); var cookieparser = require('cookie-parser'); var bodyparser = require('body-parser'); var morgan = require('morgan'); var mongoose = require('mongoose'); var passport = require('passport'); var localstrategy = require('passport-local').strategy; var session = require('express-session'); var socket = require('socket.io');  // var routes var index = require('./routes/index'); var users = require('./routes/users'); var projects = require('./routes/projects'); var messages = require('./routes/messages')(io);  var app = express();  // socket.io  var io = socket(); app.io = io;  io.on( "connection", function( socket ) {     console.log( "a user connected" ); });  // para devolver estado por consola. app.use(morgan('combined')); // view engine setup app.set('views', path.join(__dirname, 'views')); app.set('view engine', 'jade'); var account = require('./models/accounts'); passport.use(new localstrategy(account.authenticate())); passport.serializeuser(account.serializeuser()); passport.deserializeuser(account.deserializeuser());  // uncomment after placing favicon in /public //app.use(favicon(path.join(__dirname, 'public', 'favicon.ico'))); app.use(logger('dev')); app.use(bodyparser.json()); app.use(bodyparser.urlencoded({ extended: false })); app.use(cookieparser()); //app.use(multer({dest : "./userfiles/projectimage"}))  app.use(express.static(path.join(__dirname, 'public')));  app.use(require('express-session')({     secret: 'secretpass',     resave: true,     saveuninitialized: true,     cookie: { maxage : 3600000 } //1 hour }));  app.use(passport.initialize()); app.use(passport.session()); //rutas express app.use('/', index); app.use('/user', users); app.use('/project', projects); app.use('/message', messages)  // catch 404 , forward error handler app.use(function(req, res, next) {   var err = new error('not found');   err.status = 404;   next(err); });  // error handlers  // development error handler // print stacktrace if (app.get('env') === 'development') {   app.use(function(err, req, res, next) {     res.status(err.status || 500);     res.render('error', {       message: err.message,       error: err     });   }); }  // production error handler // no stacktraces leaked user app.use(function(err, req, res, next) {   res.status(err.status || 500);   res.render('error', {     message: err.message,     error: {}   }); });  mongoose.connect('mongodb://localhost/db');    module.exports = app; 

in app.js have code:

var messages = require('./routes/messages')(io);  var app = express();  // socket.io  var io = socket(); app.io = io; 

you should initialize io variable before passing messages export function - so:

var app = express();  // socket.io  var io = socket(); app.io = io;  var messages = require('./routes/messages')(io);